Chiral phosphine-phosphoramidite ligands for highly enantioselective hydrogenation of N-arylimines
作者:Qing Li、Chuan-Jin Hou、Xiao-Ning Liu、De-Zhi Huang、Yan-Jun Liu、Rui-Feng Yang、Xiang-Ping Hu
DOI:10.1039/c4ra16062b
日期:——
The asymmetrichydrogenation of N-arylimines with the chiral phosphine-phosphoramidite ligand, (Sc,Sa)-PEAPhos 2b, has been developed. The results revealed that the presence of the substituents on the 3,3′-positions of the binaphthyl backbone significantly improved the enantioselectivity. The utility of this methodology was demonstrated in the synthesis of the chiral fungicide (R)-metalaxyl.
Chiral Phosphine–Phosphoramidite Ligands for Highly Efficient Ir-Catalyzed Asymmetric Hydrogenation of Sterically Hindered <i>N</i>-Arylimines
作者:Chuan-Jin Hou、Ya-Hui Wang、Zhuo Zheng、Jie Xu、Xiang-Ping Hu
DOI:10.1021/ol301618r
日期:2012.7.6
A mild and general iridium-catalyzed, highly enantioselective hydrogenation of sterically hindered N-arylimines with a new H8-BINOL-derived phosphine–phosphoramiditeligand has been developed. The present catalytic system features high turnover numbers (up to 100000) and good to perfect enantioselectivities (up to 99% ee) for the hydrogenation of a variety of sterically hindered N-arylimines.